Hi. I'm in the process of buying my first RRS. I'm planning to swap the factory exhaust for something more spirited. Anyone have any experience to share - or, I'm guessing this isn't the first time this has come up, an older thread to point me to? (I've looked.) Fabspeed, Soul and Quicksilver seem like my front-runners right now. And I've had good non-RR experiences w/ Fabspeed and Soul. Thanks in advance.